Having a stressful day? Chill out with these three stress-busting snacks:Blueberries. These tiny blue wonders are rich in antioxidants, nutrients that fight off free radicals and oxidative stress, which impedes your body’s functions. In fact, when it comes to battling free radicals, blueberries are one of the toughest fighters over most other fruits or vegetables. Reducing oxidative stress and free radical build-up is key to your long-term wellness. Chicken Breast. The amino acid tryptophan has been scientifically proven to have a relaxing effect on the mind and the body. Snacking on foods high in tryptophan, such as sliced chicken breast, increases blood levels of the "relaxation" hormones serotonin and melatonin, and helps to take you to a tranquil, more restful place.Broccoli. This tree-like veggie (and other green veggies) are rich in magnesium, a micronutrient that is known as the leading stress-busting mineral. Magnesium deficiency has been linked to high stress levels, so it's important that you get adequate amounts of this nutrient. If the idea of snacking on raw broccoli isn't particularly appealing, try dipping your green veggies in a very low-calorie snack dip for added flavor.